Toothed belt attachment

ABSTRACT

The invention relates to an attachment for securing an end-part of a toothed belt-element (12, 14) to a machine element (10). The machine element (10) has a slot (18, 16) for receiving an end-part of the belt-element. Arranged on at least one of the opposing walls of the slot is at least one gripping bar (22, 28) which projects into the slot and the cross-sectional shape of which corresponds generally to the cross-sectional shape of a tooth-space formed recess (24, 30) in the end-part (14a, 12a) of the belt element.

The present invention relates to a device for fastening one end-part ofat least one toothed belt-element to a machine element which has atleast one slot through which one end-part of the belt-element isintended to be inserted and secured and the distance between the wallsof which slot correspond generally to the thickness of the belt-element.

When fastening toothed belt-elements to a machine part, for instance toa slide which is intended to movably support a read head in printingequipment, the end-part of the belt-element has previously been securedto the slide by passing said end through a slot and then securing saidend with the aid of a screw which is inserted through the slot andthrough a hole in the belt-element and then screwed into a threaded holein the slide. This belt-securing technique requires the provision of ahole in the end of the belt and also the provision of a screw-threadedhole in the slide, and also requires manual tightening of the fastenerscrew.

An object of the present invention is to provide a simpler and quickermethod of securing a toothed belt-element to a machine element withoutrequiring the provision of additional fastener elements.

This object is achieved with a belt attachment device of theaforedescribed kind which is characterized in that at least one of theopposing walls of the slot has at least one gripping bar which projectsinto the slot and the cross-sectional shape of which correspondsgenerally to the cross-sectional shape of a tooth-space formed recess inthe end-part of the belt-element. A slot of this configuration willenable the end-part of the toothed belt-element to be readily insertedinto the slot from either side thereof, i.e. transversely to the lengthdirection of the belt-element, such that the gripping bar or bars willbe placed in or inserted in tooth-space formed recesses between theprojections on the end-part of the belt-element, said projections havingthe form of rack teeth, so as to obtain a clamping fit between thebelt-end and the slot walls. In this regard, at least one wall of theslot is conveniently formed by one side wall of a tongue-like leg whichis configured to exert on the end-part of the belt-element inserted inthe slot a clamping force directed which acts in a direction towards theother side of the slot. Furthermore, it is preferred that severalgripping bars are disposed on the slot wall at a mutual distance apartwhich corresponds to the division or pitch of the toothed slots on thebelt-element, so as to ensure that a strong and stable belt-elementattachment will be ensured.

Each slot may be provided with abutment means for restricting lateralmovement of the belt-element in the attachment device.

The invention will now be described in more detail with reference to theaccompanying drawing, which is a side view illustrating a machineelement having an inventive toothed belt attachment at each end of themachine element, prior to fitting the respective toothed belts together.

The illustrated machine element is a reciprocatingly movable slide 10which is intended to carry a read head (not shown) in a printer unit.The slide 10 is driven by a toothed belt 12 which is connected at alocation (not shown) with a broader belt-element 14 which has generallythe form of a toothed belt and which, at the same time, forms ajalousie-like belt which is intended to cover a read gap for the readhead in an inoperative, parking position of the slide 10. The belt 14and the belt 12 thus form a closed loop with the slide 10.

In order to enable the belt 14 to be attached to the belt 12 quickly andsimply without requiring additional fastener elements, the slide 10 isprovided with a slot 16, 18 at each end of the slide. The slide 16 has awall which is defined by a tongue-like leg 20, and an opposing wallwhich includes two gripping bars 22 which project into the slot 16. Thespacing of the gripping bars 22 and their cross-sectional shapescorrespond to the cross-sectional shapes and the pitch of the toothinterspaces 24 located between teeth-forming rib elements 26 on thebelt-element 14. The distance between the opposing walls of the slot 16corresponds generally to the thickness of the belt 14. Thus, whensecuring the belt 14 in the slot 16, the end-part 14a is inserted fromone side-opening of the slot 16, i.e. in a direction transversely to thelength direction of the belt 14, wherewith the gripping bars 22 slideinto the tooth spaces 24 with a close fit. The intrinsic resilience ofthe material of the leg 20 is also utilized to positively hold andsecure the belt-end 14a in its inserted position in the slot 16.

Similarly, the other slot 18 intended for the drive belt 12 includes aplurality of gripping bars 28 on one wall of the slot, thecross-sectional shape and the mutual spacing of these bars correspondingto the cross-sectional shape and the pitch for mutual spacing of thetooth interspaces 30 of the toothed belt 12. A tongue 32 defines theother wall of the slot 18 and exerts an adequate clamping force on theend-part 12a of the toothed belt 12 when said end-part is inserted intothe slot 18 from one side thereof.

Each of the slots 16, 18 may be provided with suitable abutment meansfor restricting lateral movement of the belt-element and toothedbelt-element 14, 12 in the attachment 10. In the illustrated embodiment,the tongue 32 is provided with two upwardly projecting side-legs 34between which the toothed belt 12 is guided.

I claim:
 1. A device for attaching an end-part of at least one toothedbelt-element to a machine element which has at least one slot in whichthe end-part of the belt-element is intended to be inserted and secured,and where the distance between the opposing walls of the slot generallycorresponds to the thickness of the belt-element, characterized in thatat least one of the opposing walls of the slot includes at least onegripping bar which projects into the slot and the cross-sectional shapeof which corresponds generally to the cross-sectional shape of atooth-space formed recess in the belt-element end-part, in that at leastone wall of the slot forms one side-wall of a tongue-like leg which isconfigured to exert on the end-part of the belt-element inserted in saidslot a clamping force which acts in a direction towards the other wallof the slot and in that the slot is such that the belt-element end-partcan be inserted into the slot in s direction transverse to the length ofthe belt-element.
 2. A device according to claim 1, characterized inthat a plurality of gripping bars are disposed on the said at least oneslot wall at a mutual spacing which corresponds to the pitch or divisionof the tooth spaces on the belt-element respectively.
 3. A deviceaccording to claim 1, characterized in that the slot includes abutmentmeans which function to limit lateral movement of the belt-element insaid device.